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Spectral saturation: inverting the spectral Turan theorem

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 نشر من قبل Vladimir Nikiforov
 تاريخ النشر 2007
  مجال البحث
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We prove that if the spectral radius of a graph G of order n is larger than the spectral radius of the r-partite Turan graph of the same order, then G contains various supergraphs of the complete graph of order r+1. In particular G contains a complete r-partite graph of size log n with one edge added to the first part. These results complete a project of Erdos from 1963. We also give corresponding stability results.



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